Currently, trying to serialize an object that can’t be serialized will fail with a short error message. For example, the diff and the error message:
0diff --git a/src/test/serialize_tests.cpp b/src/test/serialize_tests.cpp
1index d75eb499b4..773f49845b 100644
2--- a/src/test/serialize_tests.cpp
3+++ b/src/test/serialize_tests.cpp
4@@ -62,6 +62,8 @@ public:
5
6 BOOST_AUTO_TEST_CASE(sizes)
7 {
8+ int b[4];
9+ DataStream{} << b << Span{b};
10 BOOST_CHECK_EQUAL(sizeof(unsigned char), GetSerializeSize((unsigned char)0));
11 BOOST_CHECK_EQUAL(sizeof(int8_t), GetSerializeSize(int8_t(0)));
12 BOOST_CHECK_EQUAL(sizeof(uint8_t), GetSerializeSize(uint8_t(0)));
0./serialize.h:765:6: error: member reference base type 'const int[4]' is not a structure or union
1 765 | a.Serialize(os);
2 | ~^~~~~~~~~~
0./serialize.h:277:109: error: no matching function for call to 'UCharCast'
1 277 | template <typename Stream, typename B> void Serialize(Stream& s, Span<B> span) { (void)/* force byte-type */UCharCast(span.data()); s.write(AsBytes(span)); }
2 | ^~~~~~~~~
This is fine. However, it would be more helpful for developers and more accurate by the compiler to explain why each function is not selected.
Fix this by using C++20 concepts where appropriate.
